The present invention relates to a process for the industrial synthesis of strontium ranelate of formula (I):
(the distrontium salt of 5-[bis(carboxymethyl)amino]-3-carboxymethyl-4-cyano-2-thiophenecarboxylic acid), and its hydrates.
Strontium ranelate has very valuable pharmacological and therapeutic properties, especially pronounced anti-osteoporotic properties, making this compound useful in the treatment of bone diseases.
Strontium ranelate, its preparation and its therapeutic use have been described in the European Patent Specification EP 0 415 850.
However, industrial production of a compound such as strontium ranelate requires detailed study of all the reaction steps and of the selection of starting materials, reagents and solvents in order to obtain optimum yields.
The Applicant has developed a synthesis process for strontium ranelate of formula (I) in which such conditions have been combined, resulting in the use of a whole group of especially valuable methods and procedures.